Why do we have an appendix?

If we can remove your appendix why we all have one anyways?  Read the following article:  What the appendix is good for - Some body parts seem pointless but in fact have purpose, by Emily Sohn.

What is a vestigial organ?  Why do we have an appendix, what does it do?  Why does living in undeveloped ntries versus living in the US matter - what does this have to do with your appendix?  What are some of our other vestigial organs and why do we have them?

Importance of Fiber in your Diet

Today we studied the digestive system.  An important part of your diet is fiber.  But fiber can not be digested.... so why do we need fiber?  Read the following article:  Are You Getting Enough Fiber?  by Mitzi Dulan. 

Why is fiber important in your diet?  What is soluble fiber?  Insoluble fiber?  How can you get more fiber in your diet?